Oil pressure safety device



March 29, 1960 F. GOOD oIL PRESSURE SAFETY DEVICE Filed May l2, 1958 m N- .Iza

INVENTOR.

FLOY D G O O D United.

OIL PRESSURE SAFETY DEVICE Floyd Good, Sterling, Ill.

Application May 12, 1958, Serial No. 734,560

2 Claims. (Cl. 340-52) This invention relates to internal combustion engines and more particularly to a safety device therefor.

It is an object of the present invention to provide an oil pressure safety device for use with all types of gasoline and Diesel internal combustion engines that will prevent accident-al damage to the engine caused by a lack of proper oil pressure.

Another object of the present invention is to provide an oil pressure safety device of the above type that will instantly produce a signal when the pressure of the oil in the engine falls below a predetermined minimum value, which devicev is automatically deenergized in response to the interruption of the operation of the engine.

Other objects of the invention are to provide an oil pressure safety device bearing the above objects in mind which is of simple construction, has a minimum number of parts, is inexpensive to manufacture and efficient in operation.

For other objects and for a better understanding of the invention, reference may be had to the following detailed description taken in conjunction with the accompanying drawing, in which:

The drawing shows a schematic diagram of an oil pressure safety device made in accordance with the present invention.

Referring now more in detail to the drawing, an oil pressure safety device made lin accordance with the present invention is shown to include a pressure responsive unit 12 having an expansible diaphragm 13 connected to the oil pump P of the engine 16 by means of a connecting pressure line 15. A lever 18 pivotally connected by means of apin 19 upon the pressure unit 12 is connected at its mid portion to the expansible diaphragm 13. This lever 18 is an electrical conductor and has a contact 20 at its free end that is normally in closed circuit relationship with a terminal 22 of an electrical supply line 23;' A compression `spring 17 normally ybiases the lever 18 toward this normal closed position.

A battery 25, signal lamp 26, and audible signal device 27 are also connected in series circuit relationship in the supply line 23. The terminal 29 of this supply line is disposedwithin a vacuum responsive unit 30 Ahaving a similar expansible diaphragm 31 which is connected by means of a supply line 33 to the vacuum side of the engine fuel pump 34. A lever 35, which is also an electrical conductor, is pivotally supported by means of a pivot pin 37 adjacent to the diaphragm 31, while the mid portion of this lever is connected to the outside of the diaphragm 31. The free end of the lever 35 is provided with a contact 36 that is normally maintained in open circuit relationship with the terminal 29 by the compression spring 38 acting thereagainst. The pressure and vacuum units are secured to electrical ground through mounting bolts B and other suitable means.

In actual use, the device is connected to any internal combustion engine, gasoline or diesel, by connecting the pressure line to the oil pump P of the motor 16 and the vacuum line 33 to the pressure vacuum side of the "ice of vacuum in the line 33 permits the diaphragm 31 to expand to its normal state against the action of the spring 38, thus opening the contact 36 and terminal 29 soas to deenergize the entire circuit. When the engine is operating, the vacuum in the line 33 caused by the operation of the fuel pump causes the contacts 36, 29 to close by the contraction of the diaphragm 31 and the action of the spring 38. Also, while the engine is running, oil pressure in the line 15 is operative to expand the diaphragm 13 to urge the contact 20 out of closing engagement with the terminal 22. However, as soon as the pressure in the line 15 falls beyond a predetermined minimum, the spring 17 is operative to urge the Contact 20 into closing engagement with the terminal 22, thus closing the electrical circuit to energize the lamp 26 and audible signal 27 through the battery 25. This signals the operator of the engine that there is insucient oil pressure in the engine that might cause damage thereto. Thus, proper steps can be immediately taken to remedy the loss of oil pressure so as to prevent injury to the engine.

As soon as the engine is turned oli, the loss of vacuum in the line 33 is operative to open the contacts 36, 29, so as to deenergize the circuit since the loss of oil pressure in the line 15 will cause the other contacts 20, 22 to close and would thus provide a continuous warning signal even when the engine was not operating. The aforementioned arrangement precludes this so as to provide an operative and satisfactory assembly.

While various changes may be made in the detail construction, it shall be understood that such changes shall be within the spirit and scope of the present invention as dened by the appended claims.

What I claim as new and desire to protect by Letters Patent of the United States is:

l. A signalling device for an automotive vehicle comprising, in combination, a source of electrical energy, a signal device in series circuit relationship with said source of electrical energy, a tirst normally closed electric switch and a second normally open electric switch connected in series circuit relationship with said signal device, an expansible diaphragm pressure responsive means connected to said tirst switch for opening said first switch in response to a ow of pressurized engine oil delivered by an oil pump operated by the engine of the automotive vehicle, and an expansible diaphragm vacuum responsive means connected to said second switch for clos-ing said second switch in response to the vacuum in the supply line connected to the vacuum side of the fuel pump operated by said engine, whereby low oil pressure while the engine is operating will cause the first switch to close while the second switch is closed effecting the signal device to function; however, when the engine is not operating, the first switch is closed and the second switch is open and the signal device will remain non-responsive.

2. An oil pressure signalling device of the class described comprising, in combination, a source of electrical energy, a Signal device in series circuit relationship with said source of electrical energy, a tirst normally closed electric switch and a second normally open electric switch connected in series circuit relationship with said signal device, an expansible diaphragm pressure responsive means when expanded will operate and open said rst switch, said expansion is effected in response to a ow of high pressure oil delivered by an oil pump operated by the engine of the automotive vehicle associated therewith, an expansible diaphragm vacuum responsive means when non-expanded will operate and close said second switch, said vacuum responsive means being effected in response to the degree of vacuum in the vacuum line connected to the vacuum side of the engine; whereby low oil Msg-'931,011 3. 4, pressure in the supply line-while the engine is operating References" Cited in the le of'thspatent will cause the' firstY electric switch to close while the second y electric switch is closed effecting the signal device to op- UNITED STATES PATENTS crate; however, when the engine vis not operating the first 2,571,360 Hallerberg Oct. 16, 1951 electric switch isV closed because of low oil pressure` and 5 2,722,673 Turner Nov. 11, 1955 the' second electric switch is open due to low vacuum and' the signal device' remains non-responsive. 

